Peripheral suction openings in gas turbine engines

ABSTRACT

This invention relates to partial admission gas turbine engines. A gas turbine with partial admission generally comprises a compressor, a combustor, a casing, and a bladed turbine rotor disposed in the casing.

United States Patent Mittelstaedt Feb. 29,1972

[54] PERIPHERAL SUCTION OPENINGS IN GAS TURBINE ENGINES [56] References Cited UNITED STATES PATENTS 2,603,948 7/1952 Mims ..60/39.66

2,623,356 12/1952 Coanda ..60/39.5 2,626,502 1/1953 Lagelbauer ..60/39.19 X

COMBUSTOR NOZZLE 2,652,216 9/1953 Hoffman ..60/39.66 X 2,851,853 9/1958 Quick ..60/264 X FOREIGN PATENTS OR APPLICATIONS 502,414 3/1939 Great Britain ..60/39.66 451,838 2/1913 France ..60/39.l9

OTHER PUBLICATIONS Saldin, Abstract of Application Ser. No. 3040 April 10, 1951, Published in 645 O. G. 680- 1.

Primary Examiner-Douglas Hart [5 7] ABSTRACT This invention relates to partial admission gas turbine engines. A gas turbine with partial admission generally comprises a compressor, a combustor, a casing, and a bladed turbine rotor disposed in the casing.

11 Claims, 3 Drawing Figures 5-TURB|NE ROTOR SCAVENGING ZONE I 3-COMBUSTOR COMPRESSOR-2 l SUCTION OPENING Patented Feb. 29, 1972 /5 -TURBINE ROTOR \SUCTION OPENING COMPRESSOR-2 SCAVENGING ZONE SCAVENGING ZONE NOZZLE-4 COMBUSTOR sucnom OPENING COMPRESSOR-2 COMPRESSED AIR NOZZLE INVENTOR.

PERIPHERAL SUCTION OPENINGS IN GAS TURBINE ENGINES In the present invention, a peripheral opening extends through the casing outwardly of and in the plane of the turbine rotor, and opens to atmosphere; a power-inducer nozzle e.g., a combustor nozzle is disposed immediately downrotation of the peripheral opening and is directed to the turbine blades; a suction zone is provided immediately uprotation of the power-inducer nozzle; and a scavenging zone is provided immediately downrotation of the power-inducer nozzle.

The power-inducer nozzle is disposed between the suction zone and the exhaust zone.

The gases issuing from the power-inducer nozzle, the rotating turbine blades, the suction zone, and the scavenging zone, together, induce a suction flow of atmospheric air through the peripheral opening to the turbine blades. A cooling effect is secured on the turbine blades as they pass through the suction zone, and the total mass of air intake and exhaust is augmented.

This invention relates to gas turbine engines and particularly to partial admission gas turbine engines in which atmospheric air is drawn to the turbine blades through a peripheral opening in the casing.

The'peripheral opening is uprotation of a power-inducer nozzle, downrotation of a blade scavenging zone, and outward of and in the plane of the turbine blades. The opening is part of a suction zone and opens directly to atmosphere.

The' power-inducer nozzle comprises a combustor outlet nozzle directed to the turbine blades downrotation of the peripheral opening. The gases issuing from the power-inducer nozzle drive the turbine rotor and also are instrumental in inducing suction flow through the peripheral opening. A compressor nozzle may form part of the power-inducer nozzle.

In the blade scavenging zone, pressure gases remaining between the turbine blades downrotation of the power-inducer nozzle are expelled. Pressure in a peripheral suction zone would counteract peripheral suction.

In this invention, the rotating turbine blades, the power-inducer nozzle, the blade scavenging zone and the peripheral suction zone, together, produce effective suction flow through the peripheral opening into the casing and to the turbine blades as they pass through the suction zone. Then the peripheral air is moved rearward.

The peripheral air is atmospheric and will secure a fresh-air cooling effect, especially on the extreme blade tips, and will augment the total mass of the air intake and of the exhaust.

If a compressor nozzle constitutes part of the power-inducer nozzle, direct front cooling of the turbine blades will also be effected.

With this cooling device, the engine can be operated at higher temperatures than without, thereby increasing power and improving efficiency, and in some engines e.g.,jet engines also increasing exhaust velocity and thrust. Besides, more ordinary turbine blade material can be used, thereby reducing initial cost and maintenance.

Therefore, the main objects of this invention are to operate the engine at higher temperatures to obtain maximum efficiency, to secure a cooling effect in the blade zone and even to cool the extreme blade tips, to augment the total mass of the air intake,'to augment the total mass of the exhaust, and to use relatively ordinary turbine blade material.

These and other objects are apparent in the description, in which characters of reference refer to like named parts in the drawing.

The drawing is schematic and shows plan views illustrating the invention, but the invention is not limited to the particular construction shown. 7

Referring briefly to the drawing,

FIG. 1 illustrates an embodiment of the invention, showing a combustor nozzle as power-inducer nozzle. v

FIG. 2 shows a compressor nozzle, as part of .a power-inducer nozzle.

FIG. 3 also shows a pressure air emitting nozzle as part of a power-inducer nozzle.

All Figures are basically the same, and the basic parts and features will be given the same numerals in all Figures, as is practicable.

Referring in greater detail to the drawing, the numeral 1 in FIG. 1 indicates the casing of a gas turbine engine. The numeral 2 indicates a compressor furnishing compressed air at least partly for use in the combustor 3. In the combustor, the compressed air is mixed with fuel and is ignited. This is well known and is not shown. The numeral 4 indicates a combustor outlet nozzle which also serves as turbine inlet nozzle, directing the combustion gases to the blades of turbine wheel 5. The combustion gases drive the turbine wheel, and the turbine wheel drives the compressor 2 throughthe drive shaft 6. The bracketted area 7 indicates the described blade scavenging zone, and the dotted line 8 indicates the described peripheral suction zone and -opening in the turbine casing. The combustor nozzle 4 is located between the peripheral opening 8 and the scavenging zone 7. The peripheral opening is outward of and in the plane of the turbine blades, and opens directly to atmosphere. The arrow 9 indicates the direction of rotation, and the numeral 10 indicates a transverse plate or other barrier both uprotation and downrotation of the power-inducer nozzle, uprotation to provide a peripheral suction zone, and downrotation to provide a blade scavenging zone.

During operation, the nozzle 4 directs the combustion gases to the turbine blades, thereby driving the turbine. In its location between blade scavenging zone and peripheral suction opening; the nozzle 4 also acts as inducer nozzle and is instrumental in inducing the described peripheral suction flow. Therefore the nozzle 4 is a power-inducer nozzle forming the power-inducer zone. The pressure gases remaining between the blades after the power-inducer stroke (or zone) are expelled in the bracketted scavenging zone 7.

The power-inducer nozzle, the rotating turbine blades, the peripheral suction zone and the blade scavenging zone, together, produce the suction flow through the peripheral opening 8 into the turbine casing and to the turbine blades.

A cooling effect will be provided in the turbine, and the extreme blade tips will be cooled with fresh atmospheric air.

With this cooling device, the engine can be operated at higher temperatures than without cooling, resulting in greater power and higher efficiency.

FIG. 2 is similar to FIG. 1, but here a compressor nozzle forms part of the power-inducer nozzle. The numeral 11 indicates a duct from compressor 2, ending in the nozzle 12 directed to the turbine blades. The compressor nozzle 12 is immediately uprotation of the combustor nozzle 4 and immediately downrotation of the peripheral opening 8. In this position, the compressor nozzle 12 is an inducer nozzle and is instrumental in inducing suction flow through the peripheral opening 8. Again, the numeral 7 indicates the blade scavenging zone, and 10 indicates transverse barrier means. The combustor nozzle 4 will also act to some degree to induce suction flow through the peripheral opening 8.

FIG. 3 is similar to FIG. 2 in that a compressed air emitting nozzle forms part of the power-inducer nozzle. Here, an outlet 13 from the compressor 2 furnishes pressure air to the area outside the combustor, and such pressure air is passed through the nozzle 14 to the turbine blades. The nozzle I4 is immediately uprotation of the combustor nozzle 4 and immediately downrotation of the peripheral opening 8. In this position, the pressure air-emitting nozzle l4 is an inducer nozzle and is instrumental in inducing suction flow through the peripheral opening 8 into the turbine casing. Again, the numeral 7 indicates the blade scavenging zone, and the numeral 10 indicates a transverse barrier in front of the'turbine-blades in the peripheral suction and scavenging zones. In this Figure too, the combustor nozzle 4 will act to some degree to induce suction flow through the peripheral opening 8.

In the drawing, a turbine blade will first pass across the peripheral-opening zone, then across the power-inducer zone and then-across the blade-scavenging zone. Then the cycle is repeated.

In the blade-scavenging zone, the action of the blades is instrumental in expelling pressure gases from between the blades.

There may be plural power-inducer nozzles, with the described peripheral suction openings immediately uprotation of the nozzles. Here, the power-inducer nozzles must be spaced far enough apart to allow for both peripheral suction zones and blade scavenging zones.

The turbine rotor(s) may drive any load(s) besides driving the compressor, and the gas turbine engine can have any suitable final exhaust channel, not shown. In connection with jet propulsion engines, there probably will be ajet exhaust nozzle, also not shown.

ln the text and claims, by "blade is meant turbine rotor blade; by uprotation is also meant on the blade entering side of, rotationally upward of; by downrotation is also meant on the blade exiting side of, rotationally downward of; by scavenging zone" or blade scavenging zone is meant the zone downrotation of the power-inducer nozzle, where the pressure gases remaining between the blades after the powerinducer stroke are removed as is practicable; by combustor nozzle or power nozzle" is meant combustion gas emitting nozzle; by compressor nozzle is meant pressure air-emitting nozzle; by pressure nozzle" is meant pressure gas emittingnozzle; by inducer nozzle" is meant a nozzle being instrumental in effecting the peripheral suction flow; by power-inducer stroke" or power-inducer zone" is meant blade driving and peripheral suction inducing stroke or zone; by in the plane of" is also meant partly in the plane of; by peripheral opening" is also meant peripheral suction zone opening; by in front of is also meant upstream of; by immediately is also meant closely.

Basically, this gas turbine engine may be considered to have three zones or strokes" per cycle. In the direction of rotation, if considered beginning with the peripheral suction opening, they are: l. the peripheral suction zone or stroke, to draw in peripheral air; 2. the power-inducer zone or stroke to drive the turbine, and instrumental in inducing suction flow through the peripheral opening in the suction zone; and 3. the blade scavenging zone or stroke to remove or scavenge the effective pressure gases remaining between the turbine blades downrotation of the power-inducer zone or stroke. Then a new cycle begins.

Of course, the cycle may also be considered to begin with any other stroke e.g., the power-inducer stroke or the bladescavenging stroke.

There may be only a combustor nozzle in the power-inducer zone, or plural combustor nozzles, or there may be combustor nozzle-compressor nozzle combinations in this zone. That is, in the power-inducer zone, the turbine blades may pass across the end of one combustor nozzle, or across the ends of plural combustor nozzles, or across any combination of combustor and compressed air emitting nozzles. Regardless, there always will be the described peripheral suction opening on the blade entering side of the power-inducer zone, and there will be the described scavenging zone on the blade exiting side of the power-inducer zone.

In the text and claims, by power-inducer nozzle is meant single combustor nozzle, plural combustor nozzles, or any combination of combustor and compressor nozzles; by nozzle" is also meant opening, duct; by opening" is also meant aperture, openwork, perforations, passage, duct, openings; by atmosphere is also meant air under atmospheric pressure; by "turbine or turbine wheel" is also meant bladed turbine rotor; by periphery" is also meant perimeter, circumference; by "combustor" is also meant combustion chamber, flame tube; by casing" is also meant turbine casing, turbine and fan duct casing, housing, cover.

ln gas turbine engines with plural turbine rotors, the peripheral opening through the casing is outward of and in the plane of the first rotor, and peripheral air is drawn to the blades of the first turbine rotor. Therefore, in the text and claims, by turbine rotor is also meant first turbine rotor. Also in the text and claims, by outwardly of and in the plane of the turbine rotor is also meant outward of the blade tips of the turbine rotor.

This invention can be used in any suitable partial admission gas turbine engine e.g., in industrial engines, marine engines, automobile engines, aircraft engines, jet engines etc.

In an exemplary fan-jet application, the defined peripheral opening takes the form ofa duct or passage extending through the turbine casing and through a fan duct and fan duct casing to atmosphere, atmospheric air being drawn through the duct or passagelike peripheral opening to the turbine blades. In view of this, by casing is also meant fan duct casing, turbine and fan duct casing.

All illustrated and/or described features are meant to be interchangeable.

It is to be noted that changes may be made without departing from the spirit or scope of the invention.

1 claim:

1. [ti a partial admission gas turbine comprising a casing, a turbine rotor with turbine blades disposed in the casing, a combustor furnishing combustion gases, and a compressor furnishing compressed air at least partly for use in the combustor, a peripheral opening extending through the casing outwardly of and in the plane of the turbine rotor and opening to atmosphere, a power-inducer nozzle issuing gases under pressure disposed downrotation of the peripheral opening and directed to the turbine blades, wall means uprotation of the power-inducer nozzle providing a suction zone, and wall means downrotation of the power-inducer nozzle providing a scavenging zone; the turbine rotor being rotated, and atmospheric air being drawn through said peripheral opening to the turbine blades as they pass through the suction zone; the gases issuing from the power-inducer nozzle driving the turbine rotor and being a factor in inducing the suction flow through the peripheral opening.

2. A gas turbine according to claim 1, said power-inducer nozzle comprising a combustor nozzle disposed between said peripheral opening and said scavenging zone and directed to the turbine blades.

3. A gas turbine according to claim 1 said power-inducer nozzle comprising plural combustor nozzles disposed between said peripheral opening and said scavenging zone and directed to the turbine blades.

4. A gas turbine according to claim 1, said power-inducer nozzle comprising a combustor nozzle and a compressor nozzle, disposed between said peripheral opening and said scavenging zone and directed to the turbine blades.

5. A gas turbine according to claim I, said power-inducer nozzle comprising a combination of combustor nozzles and compressor nozzles, disposed between said peripheral opening and said scavenging zone and directed to the turbine blades.

6. A gas turbine according to claim 1, the gases issuing from the power-inducer nozzle, the rotating turbine blades, the suction zone, and the scavenging zone, together, inducing a suction flow of atmospheric air through said peripheral opening to the turbine blades.

7. A gas turbine according to claim 1, wherein the inner end of the peripheral opening faces the turbine blades radially, the outer end of the peripheral opening communicating with atmosphere.

8. A gas turbine according to claim 1, wherein the power-inducer nozzle is immediately between said peripheral opening and said scavenging zone.

9. gas turbine according to claim 1, wherein said peripheral opening is immediately uprotation of the power-inducer nozzle, and the scavenging zone is immediately downrotation of the power-inducer nozzle.

10. In a gas turbine according to claim 1, a forward extension of said peripheral opening beyond the turbine blades.

11. In a gas turbine according to claim 1, a rearward extension ofsaid peripheral opening beyond the turbine blades.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 a 645 096 Dated February 29 1972 Georg S. Mittelstaedt Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the cover sheet, "[57]" ABSTRACT" should appear as shown below ABSTRACT This invention relates to partial admission gas turbine engines. A gas turbine with partial admission generally comprises a compressor, a combustor, a casing, and a bladed turbine rotor disposed in the casing.

In the present invention, a peripheral opening extends through the casing outwardly of and in the plane of the turbine rotor, and opens to atmosphere; a power-inducer nozzle e.g. a combustor nozzle is disposed immediately downrotation of the peripheral opening and is directed to the turbine blades; a suction zone is provided immediately uprotation of the power-inducer nozzle; and a scavenging zone is provided immediately downrotation of the powerinducer nozzle.

The power-inducer nozzle is disposed between the suction zone and the exhaust zone.

The gases issuing from the power-inducer nozzle, the rotating turbine blades, the suction zone, and the scavenging zone together, induce a suction flow of atmospheric air through the peripheral. opening to the turbine blades. A cooling effect is secured on the turbine blades as they pass through the suction zone, and the total mass of air intake and exhaust is augmented.

Column 1, lines 3 through 19 should be canceled.

Signed and sealed this 20th day of February 1973.

LSEAL) Attest:

EDWARD 'M.FLETCI'IER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents FORM PO-IOSO (IO-69) USCOMM-DC 60376-P69 a 0.5. GOVERNMENT PRINTING OFFICE: I969 0-366-334. 

1. In a partial admission gas turbine comprising a casing, a turbine rotor with turbine blades disposed in the casing, a combustor furnishing combustion gases, and a compressor furnishing compressed air at least partly for use in the combustor, a peripheral opening extending through the casing outwardly of and in the plane of the turbine rotor and opening to atmosphere, a power-inducer nozzle issuing gases under pressure disposed downrotation of the peripheral opening and directed to the turbine blades, wall means uprotation of the power-inducer nozzle providing a suction zone, and wall means downrotation of the power-inducer nozzle providing a scavenging zone; the turbine rotor being rotated, and atmospheric air being drawn through said peripheral opening to the turbine blades as they pass through the suction zone; the gases issuing from the power-inducer nozzle driving the turbine rotor and being a factor in inducing the suction flow through the peripheral opening.
 2. A gas turbine according to claim 1, said power-inducer nozzle comprising a combustor nozzle disposed between said peripheral opening and said scavenging zone and directed to the turbine blades.
 3. A gas turbine according to claim 1, said power-inducer nozzle comprising plural combustor nozzles disposed between said peripheral opening and said scavenging zone and directed to the turbine blades.
 4. A gas turbine according to claim 1, said power-inducer nozzle comprising a combustor nozzle and a compressor nozzle, disposed between said peripheral opening and said scavenging zone and directed to the turbine blades.
 5. A gas turbine according to claim 1, said power-inducer nozzle comprising a combination of combustor nozzles and compressor nozzles, disposed between said peripheral opening and said scavenging zone and directed to the turbine blades.
 6. A gas turbine according to claim 1, the gases issuing from the power-inducer nozzle, the rotating turbine blades, the suction zone, and the scavenging zone, together, inducing a suction flow of atmospheric air through said peripheral opening to the turbine blades.
 7. A gas turbine according to claim 1, wherein the inner end of the peripheral opening faces the turbine blades radially, the outer end of the peripheral opening communicating with atmosphere.
 8. A gas turbine according to claim 1, wherein the power-inducer nozzle is immediately between said peripheral opening and said scavenging zone.
 9. A gas turbine according to claim 1, wherein said peripheral opening is immediately uprotation of the power-inducer nozzle, and the scavenging zone is immediately downrotation of the power-inducer nozzle.
 10. In a gas turbine according to claim 1, a forward extension of said peripheral opening beyond the turbine blades.
 11. In a gas turbine according to claim 1, a rearward extension of said peripheral opening beyond the turbine blades. 